Finding and securing Syria's chemical weapons stockpile amid a bloody civil war will be a daunting and lengthy task that will make bringing some of the world's most contentious regimes to the negotiating table look easy, experts say.

Thousands of tons of deadly weapons are spread throughout Syria, hidden in underground bunkers, secured in clandestine government facilities and constantly being moved, according an unclassified CIA report.

"We certainly know that there are challenges. There are potentially a large amount of chemical weapons in Syria's stockpile," Psaki said. "And so part of this effort is to figure out how to make the destruction effort logistically and technically possible. But we know it's -- it would be challenging."

President Barack Obama said he will consider a Russian proposal to force Syria to turn over those weapons for destruction, but none of the details about to Syria will comply have yet been determined.

"Nothing about this will be easy," said Gwyn Wifiled, editor of CBRNe World and an expert on weapons of mass destruction. "The inspectors will effectively become a third player in the conflict. It will be difficult to get to places they need to go, and they will be forced to rely on the Syrians for information and security."

The Syrians have said they are willing to give up their entire stockpile. It's unclear just how large the stockpile is, experts estimate the stockpile to be hundreds of tons, spread over perhaps a dozen locations. They say it likely includes mustard gas and the nerve agents sarin and the more deadly VX.

Although Syria said it is willing to give up its cache of weapons, it will likely take inspectors months to find out where the weapons are hidden before they step foot in Damascus, former weapons inspectors said.

Once found, weapons will take years to destroy in custom-built facilities.

"It's unlikely the world will agree to do this the quick and dirty way, taking the weapons out into the desert and burning them up, creating a huge toxic plume and making areas uninhabitable," Winfield told ABCNews.com. "Instead they will need to build a facility. That can take five to 10 years in peace time. They have to do this in the middle of a war."

It took more than a decade to destroy Iraq's stockpile. Russia and the U.S., the countries most experienced in destroying chemical weapons, are 12 years behind their commitments to destroy their own arsenals under an Organization for the Prohibition of Chemical Weapons treaty, according to the group.

Generally, the UN oversees the destruction of chemical weapons. The U.S. estimated in April that 70,000 troops would be needed to secure Syria's caches.

Charles Duelfer, a former UN weapons inspector and special advisor to the CIA, said troops were able to secure and begin destroying chemical weapons within 10 months of inspectors arriving in Bagdad. He attributes the speed to having inspectors follow up with Iraqis.

"This doesn't need to take long and doesn't need to be the way the Pentagon does things," Duelfer told ABC News. "If done properly, all obligations are on the Syrians including security. The inspectors are there in a supervisory role, but the Syrians have to declare where the weapons are and the obligation is on the Syrians to create and operate facilities to destroy them."

But two decades later, there are still weapons in Iraq waiting to be destroyed, he said.

ABC News' Christopher Good contributed to this report from Washington, D.C.